For years I thought black tie meant plain and safe, so I kept buying the same shapeless shift and standing in it feeling like a waitress. What changed my mind was borrowing a dress with a proper bias cut for a wedding, one that actually moved when I walked instead of just hanging there, and realising the dress code isn't the enemy. It's asking for something with a bit of intention behind it, not something boring.
The easiest way to wear one of these is to let it do the talking and keep everything else quiet. A simple clutch, shoes that don't fight for attention, maybe one decent piece of jewellery and that's your lot. I've learned not to layer a jacket over mine unless the weather genuinely demands it, because most black tie dresses are built to be seen whole, and a cardigan thrown over the top undoes the line you paid for. If it's a winter do and you need warmth, a proper coat worn to the door and taken off before you're seen is the move, not something half zipped over the dress all night. True black is the obvious choice and it's obvious for a reason, it photographs well and goes with anything silver or gold you already own, but I've had good luck with a very dark navy too, which reads as black tie appropriate in low light but feels slightly less funereal under daytime lighting at a drinks reception beforehand.
What separates a dress that lasts from one that dies after two wears is mostly in the finishing you don't notice until it's gone wrong. Check the lining, a good one has its own structure and doesn't cling to tights the second you sit down. Look at the zip, a cheap one will gape by the second glass of wine, a decent one has a bit of weight to it and stays shut. Seams matter more than people admit, run a finger along the inside and feel whether they're bound properly or just overlocked and left to fray. Beading and sequins should be sewn through the fabric, not just glued on a backing, because glued finishes shed everywhere and you'll be picking sequins out of a taxi for a month.
The real pleasure of a well made one is boring but true: you stop thinking about it. No tugging the hem when you sit, no checking the zip's held, no little panic in the cloakroom mirror. You just get on with the night, which is rather the point of getting dressed up in the first place.